The present invention relates to axles and differential drives for motor vehicles and more particularly, relates to an axle module with twin electronic torque management for use in a vehicle.
Torque distribution systems in automotive vehicles have been known for many years. Generally speaking, torque distribution devices either control the torque being transferred to an axle as found in an in-line Hang-on all wheel drive system, or may even control the torque being transferred to each individual wheel, as found in a twin xe2x80x9chang-onxe2x80x9d all wheel drive system. In the twin xe2x80x9chang-onxe2x80x9d all wheel drive systems there is typically a primary driven axle and a secondary driven xe2x80x9chang-onxe2x80x9d axle that is connected via a prop shaft or drive shaft and torque transfer couplings to the primary driven axle. The primary driven axle also generally includes a differential which divides the torque to the side shaft of each axle and then the wheels. The division of torque between the primary and secondary axles is completed by the torque transfer couplings which are usually integrated in the secondary axle.
A typical prior art twin Hang-on all wheel drive system provides a permanent drive primary axle. However, when the primary axle starts to slip, i.e., the wheels are on a slick road condition or loose gravel, etc., the prior art systems will apply torque to each wheel of the secondary axle until the appropriate wheel torque is achieved. This provides a traction performance advantage over in-line Hang-on torque distribution systems under slip conditions similar to that of a limited slip differential. It should be noted that the twin torque distribution systems eliminate any need for a differential gear set within the secondary axle.
However, with the increased traction performance of the prior art systems, a substantial number of draw backs are encountered such as complexity of the torque distribution system, the weight of the torque distribution system and the cost to manufacture and design such systems. Furthermore, the prior art torque distribution systems generally have axles that are bulky and difficult to package in the small area left for the drive-line systems. Furthermore, the increased cross vehicle width of most twin axles causes the inboard side shaft joints to be positioned or shifted towards the wheel, thus leading to packaging conflicts with the chassis components and an increase in joint angles which effects the efficiency and durability of constant velocity joints and the like. In the recent past there have been numerous attempts to overcome the above identified problems in the area of conventional drive-line systems. Most of these systems try to develop a method to reduce the mass, packaging requirements and joint angles of conventional axles by integrating the inboard side shaft joints and the differential housing. Some of these proposals have been successful in attempting to provide a lower weight, lower cost or smaller side shaft joint angle needed in current all wheel drive vehicles. However, no such integration with a twin axle including speed sensing or electronically controlled clutch packs, has been provided to date.
Therefore, there is a need in the art for an axle module that includes an integration of joints into a smaller package, reduced weight and lower side shaft joint angle, in combination with a torque distribution system that also still provides the improved traction performance demanded by all wheel drive systems. Furthermore, there is a need in the art for a torque distribution system that can electronically be controlled, thus providing for tuning for each desired vehicle""s handling and performance requirements and also creating a preemptive locking system for such all wheel drive systems.
One object of the present invention is to provide an improved torque distribution system.
Another object of the present invention is to provide an integrated axle module that includes twin electronic torque management units.
Yet a further object of the present invention is to reduce the weight and packaging requirements for an axle module in an automotive vehicle.
Still another object of the present invention is to provide an integrated axle module unit that reduces the side shaft joint angle between the module and wheels.
A further object of the present invention is to provide a torque distribution system that electronically controls the tuning for the desired vehicle handling and performance requirements.
Still a further object of the present invention is to provide an axle module that also is capable of twin axle preemptive locking measures.
Still a further object of the present invention is to provide an axle module that reduces packaging and increases integration of parts in a smaller unit.
To achieve the foregoing objects the axle module for use in a vehicle includes a housing wherein a shaft is rotatably supported within the housing. The axle module further includes a ring gear connected to the shaft. The axle module also includes a clutch pack housing engaged with an end of the shaft. A side shaft joint is then arranged within the clutch pack housing. A plurality of plates extend from the clutch pack housing and from the side shaft joint. The axle module further includes a side shaft connected to a side shaft joint.
One advantage of the present invention is a new and improved torque distribution device for a vehicle.
A further advantage of the present invention is that the integrated axle module improves traction while reducing the mass, weight and packaging requirements within the drive train system. A further advantage of the present invention is that the integrated axle module decreases the side shaft joint angle from the axle module to the wheels.
A further advantage of the present invention is that the axle module is capable of independently controlling each wheels"" distributed torque via a motor.
A further advantage of the present invention is that the integrated axle module can be tuned for the desired vehicles handling and performance requirements.
Yet a further advantage of the present invention is that the integrated axle module can be used as a preemptive blocking device for each axle and wheel independently of each other wheel.
Still a further advantage of the present invention is the use of the side shaft joint as an inner race of the clutch pack.
Other objects, features, and advantages of the present invention will become apparent from the subsequent description and appended claims taken in conjunction with the accompanying drawings.